Tissue collection and delivery device and methods of use thereof

ABSTRACT

A system and method for harvesting autologous tissue, mincing it into fragments that are visible and measurable when filtered, and delivering a portion of the tissue back into the patient without the need to directly touch the tissue. During the same surgical procedure, the tissue can be mixed with a biocompatible agent before introduction into the repair site.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of co-pending U.S. application Ser.No. 16/346,949, entitled TISSUE COLLECTION AND DELIVERY DEVICE ANDMETHODS OF USE THEREOF, which in turn is the U.S. national phase entryunder 35 U.S.C. § 371 of International Application No.PCT/US2019/012870, filed Jan. 9, 2019, which in turn claims priority toand benefit of U.S. Provisional Application No. 62/622,247, filed Jan.26, 2018, the contents of which are incorporated herein by reference intheir entirety for all purposes.

TECHNICAL FIELD

The present disclosure relates generally to tissue harvesting and, moreparticularly, to a device for collecting autologous tissue from asurgical site and delivering the collected material where desired.

BACKGROUND

Articular cartilage is an avascular tissue which lines the ends of thebones and facilitates frictionless movement of the joints, such as theknee joint. Damage to cartilage caused by injury or disease does notheal on its own, and the pathological changes resulting from this damagecan be a source of pain and limited mobility to a patient, and can havea significant detrimental impact on the patient's quality of life.Additionally, over time, cartilage lesions are likely to degenerate intoosteoarthritis and the need for a total joint replacement.

In some cases, tissue harvesting techniques can be used to treatcartilage lesions and postpone or obviate the need for a jointreplacement. These techniques enable a surgeon to purify a uniquepopulation of repair cells from the patient's tissues, such as synovialor adipose tissue, and deliver the cells back into the patient's jointto stimulate cartilage repair. The repair cells are harvestedarthroscopically from a site local to the defect (i.e. within thejoint), and repair cells of a desired size are isolated, for example, byfiltering. The isolated cells are typically mixed with a biocompatible“gluing” agent and the mixture of the agent and the harvested cells isthen provided to the repair site. The use of autologous tissue isparticularly desirable as it substantially reduces the potential for animmunogenic host response and tissue rejection.

Various tissue harvesting techniques for treating cartilage are known inthe art. Some examples include mosaicplasty, in which plugs of cartilageand bone are harvested from low weight-bearing regions of the joint andtransplanted into the defect; or autologous chondrocyte implantation(ACI), in which cells are isolated and expanded from a cartilage biopsyand re-introduced into the defect in a second procedure. However, someof these techniques, like ACI, involve separate surgical procedures thatoccur on two different days, which may be weeks apart. Even for singlesurgery techniques, clinical results suggest that the long-termbiochemical and biomechanical properties of the reparative tissue aregenerally not ideal.

SUMMARY

Described herein are low cost, simple, one-surgery systems and methodsfor harvesting autologous tissues from a patient and delivering theminto another area that requires repair. The system of this disclosureharvests autologous tissue, minces it into fragments that are visibleand measureable when filtered, and delivers a portion of the tissue backinto the patient. Advantageously, this is accomplished without the needto directly touch the tissue, thus eliminating the risk of diseasetransmission and immune response associated with such treatment. Duringthe same surgical procedure, the isolated cut tissue can be loaded into,or mixed with, an appropriate carrier before introduction into therepair site. The systems and methods of this disclosure advantageouslyreduce the need for multiple surgeries and also facilitate improvedlong-term recovery outcomes by efficiently harvesting and implantingautologous tissue during a single surgical procedure.

Further examples of the systems and methods of this disclosure mayinclude one or more of the following, in any suitable combination.

In examples, the tissue collection assembly of this disclosure includesa resection system having a handpiece with a proximal end, a distal end,and a passageway therethrough. The resection system also includes acannulated shaft attached to the handpiece in fluid communication withthe passageway. A distal end of the shaft has a cutting end. The tissuecollection assembly also includes a filter assembly removeably attachedto the handpiece in fluid communication with the cannulated shaft. Thefilter assembly includes a housing allowing direct visualization of aninternal volume of the housing, a filter removeably disposed within theinternal volume of the housing for collecting tissue on a surface of thefilter, and a compressor extendable through the internal volume of thehousing for compressing the collected tissue. The filter assembly iscoupleable with a delivery device to deliver the collected tissue to arepair site.

In other examples, the handpiece further includes rigid tubing and abarb in fluid communication with the filter assembly. The compressor hasan inlet for removeable attachment to the barb. The housing alsoincludes a removeable outlet for attachment to a vacuum source. Thefilter is coupled to the outlet such that the filter and the outlet areremoveable from the housing simultaneously. In examples, the housingfurther includes a shearing member slidably disposed around the filterfor removing the collected tissue from the filter. In examples, theresection system also includes a flexible shield adjacent the cuttingend of the shaft. In examples, the handpiece is a motorized drive unithaving at least one internal structure to prevent contamination of thecollected tissue by the handpiece. In examples, the at least oneinternal structure is a flow diverter or a sleeve integrated with thepassageway of the handpiece. In further examples, the tissue collectionassembly includes one or more deformable wires for mixing the collectedtissue with a biocompatible agent. The wires are attached to thecompressor or to the plunger. In examples, the filter is a hollow,tubular filter, and the surface of the filter comprises holes incommunication with an interior of the filter.

Examples of the tissue collection assembly and delivery devicecombination of this disclosure include a tissue collection assembly witha resection system having a handpiece with a proximal end, a distal end,and a passageway therethrough. The resection system also includes acannulated shaft attached to the handpiece in fluid communication withthe passageway. A distal end of the shaft has a cutting end. The tissuecollection assembly also includes a filter assembly removeably attachedto the handpiece in fluid communication with the cannulated shaft. Thefilter assembly includes a housing allowing direct visualization of aninternal volume of the housing, a filter removeably disposed within theinternal volume of the housing for collecting tissue on a surface of thefilter, and a compressor extendable through the internal volume of thehousing for compressing the collected tissue. A delivery device iscoupleable to a coupling portion of the housing for delivering thecollected tissue to a repair site. In further examples, the combinationincludes a plunger insertable through the compressor and a channel ofthe delivery device. The combination also includes an actuator foradvancing the plunger within the channel and a mechanism for controllingthe relative motion between the compressor and the plunger through aportion of the housing. The mechanism is configured to prevent theadvancement of the plunger through the housing until the compressor isstopped from advancing through the housing.

Examples of the method of collecting and delivering tissue to a repairsite of this disclosure include contacting a blade of a tissuecollection assembly with tissue and cutting the tissue with a cuttingend of the blade to create tissue fragments. The method also includesaspirating fluid and the tissue fragments through the blade to a filterassembly. The filter assembly includes a housing allowing directvisualization of an internal volume of the housing, the housing in fluidcommunication with the blade, a filter removeably disposed within theinternal volume of the housing for collecting the tissue fragments on asurface of the filter, a compressor extendable through the internalvolume of the housing for compressing the tissue fragments, and ashearing member slidably disposed around the filter for removing thecollected tissue from the filter. The method also includes separatingthe tissue fragments having a pre-selected size from the fluid using thefilter and detaching the filter assembly from the blade. In examples,the method also includes removing the filter from housing, therebycausing the shearing member to shear the tissue fragments from thesurface of the filter, and coupling the filter assembly to a deliverydevice. Finally, examples of the method include inserting a plungerthrough the filter assembly and the delivery device to deliver thetissue fragments to a repair site.

Further examples of the method include extending the compressor withinthe housing to compress the tissue fragments such that a volume of thetissue fragments is measureable by direct visualization. In examples,the method also includes injecting a biocompatible agent into thehousing and rotating one or more deformable wires attached to thecompressor or the plunger to mix the tissue fragments and the agent. Inexamples, the method also includes actuating an actuator on the deliverydevice to advance the plunger within a channel of the delivery device.

Other examples of a resection system of this disclosure include ahandpiece having a proximal end, a distal end, and a passagewaytherethrough. Examples of the resection system also have a cannulatedshaft attached to the handpiece in fluid communication with thepassageway. A distal end of the shaft has a cutting end. In examples,the resection system also includes a filter removeably disposed withinthe shaft between the handpiece and the cutting end for collectingtissue on a surface of the filter.

These and other features and advantages will be apparent from a readingof the following detailed description and a review of the associateddrawings. It is to be understood that both the foregoing generaldescription and the following detailed description are explanatory onlyand are not restrictive of aspects as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will be more fully understood by reference to thedetailed description, in conjunction with the following figures,wherein:

FIG. 1 illustrates an exemplary tissue collection assembly of thisdisclosure;

FIGS. 2A and 2B are detailed views of the cutting end of the tissuecollection assembly of FIG. 1;

FIGS. 3A-G are detailed views of various examples of the handpiece andblade of the tissue collection assembly of FIG. 1;

FIGS. 4A and 4B are detailed views of an exemplary filter assembly ofthe tissue collection assembly of FIG. 1;

FIGS. 5A-C illustrate removal of the filter from the filter assembly ofFIG. 4A;

FIGS. 6A-C are detailed views of exemplary mixing elements of the tissuecollection assembly of FIG. 1;

FIGS. 7A and 7B illustrate an exemplary tissue collection and deliverydevice of this disclosure in an exploded view (FIG. 7A) and an assembledview (FIG. 7B);

FIG. 7C illustrates an alternative example of the delivery device ofFIG. 7A;

FIGS. 8A and 8B are detailed views of an actuator and plunger interfaceof the device of FIG. 7B;

FIGS. 9A-C and FIGS. 11A-C are detailed views of the control mechanismbetween the plunger and the compressor of FIG. 7B;

FIGS. 10A and 10B illustrate alternative examples of the mixing elementsof FIG. 6A;

FIGS. 12A and 12B illustrate an exemplary method of using the tissuecollection and delivery device of FIG. 7A;

FIG. 13 illustrates an alternative example of the filter of FIG. 4A;

FIGS. 14A and 14B illustrate another example of the filter of FIG. 4A;and

FIGS. 15A-C illustrate another example of the mixing elements of FIGS.10A-C and the control mechanism of FIGS. 9A-C.

DETAILED DESCRIPTION

In the description that follows, like components have been given thesame reference numerals, regardless of whether they are shown indifferent examples. To illustrate example(s) in a clear and concisemanner, the drawings may not necessarily be to scale and certainfeatures may be shown in somewhat schematic form. Features that aredescribed and/or illustrated with respect to one example may be used inthe same way or in a similar way in one or more other examples and/or incombination with or instead of the features of the other examples.

As used in the specification and claims, for the purposes of describingand defining the invention, the terms “about” and “substantially” areused to represent the inherent degree of uncertainty that may beattributed to any quantitative comparison, value, measurement, or otherrepresentation. The terms “about” and “substantially” are also usedherein to represent the degree by which a quantitative representationmay vary from a stated reference without resulting in a change in thebasic function of the subject matter at issue. “Comprise,” “include,”and/or plural forms of each are open ended and include the listed partsand can include additional parts that are not listed. “And/or” isopen-ended and includes one or more of the listed parts and combinationsof the listed parts.

Referring now to FIG. 1, an example of a tissue collection assembly 100of this disclosure is shown in an assembled view. The assembly 100generally comprises a surgical resection system 102 used to cut orresect bodily tissue from a donor site. Alternatively, other cuttinginstruments, such as a burr (not shown), may be used. The resectionsystem 102 is in fluid communication with a filter assembly 120 forisolating the tissue fragments which have been aspirated through theresection system 102. Notably, while this disclosure relates primarilyto cartilage repair, the tissue collection assembly 100 of thisdisclosure can be used for harvesting various autologous tissue types(e.g., cartilage, bone, fat, meniscus, tendon, ligament, etc.) in arange of surgical or cosmetic applications.

Still referring to FIG. 1, the resection system 102 includes a surgicalblade 103 comprising a cannulated shaft 104, and a handpiece 122 coupledto the shaft 104 via a hub 124. The shaft 104 has a proximal end 104 acoupled to the hub 124 and a distal end defining a cutting end 104 b.The handpiece 122 provides a pathway for fluid and tissue fragments toflow from the cutting end 104 b of the shaft 104 to the filter assembly120. In examples, the handpiece 122 is a motorized drive unit includinga suction lever 106 to control the flow of the tissue fragments throughthe handpiece 122. In examples, the handpiece 122 includes a rigid tube131 with a barb 132 in fluid communication with the filter assembly 120.

The filter assembly 120 comprises a substantially cylindrical housing134 with an outlet 138 removeably attached to the housing 134 forconnecting the housing 134 to a vacuum source (not shown). In examples,the vacuum source is a vacuum pump or other suitable apparatus forproviding aspiration during the surgical procedure. An inlet 136 isformed integrally with a compressor 142 which at least partially extendsthrough a port 135 in the housing 134. The inlet 136 is configured to beremoveably coupled to the barb 132. In examples, the inlet 136 and thebarb 132 are connected by flexible tubing (not shown). The inlet 136 andthe body of the compressor 142 are configured to axially slide withinthe internal volume 133 of the housing toward the outlet 138. Thus, adiameter of the port 135 is selected to accommodate the passing of bothof the inlet 136 and the compressor 142 through at least a portion ofthe housing 134.

The cutting end 104 b of the shaft 104 is shown in greater detail inFIGS. 2A and 2B. As illustrated in FIG. 2A, the cutting end 104 b of theshaft 104 includes a cutting edge 116 for fragmenting soft tissue orbone. The shaft 104 furthermore defines an aspiration lumen 126 (FIG.2B) communicating with the cutting edge 116 to remove the fragmentedtissue and fluid from the surgical site. In examples, the cutting end104 b of the shaft 104 includes an external shield 118 removeablydisposed around the shaft 104 adjacent to the cutting edge 116. Theshield 118 is configured to minimize the amount of foreign materialbeing sucked into the lumen 126. Preferably, the shield 118 is anelastomeric shield that minimizes ingestion of material which is notdirectly in front of the lumen 126. Advantageously, the pliable natureof the shield 118 minimizes interference with the mobility of the shaft104 during use.

Turning now to FIG. 3A, an exemplary handpiece 122 of this disclosure isillustrated in a cross-sectional view. In FIG. 3A, it can be seen thatthe hub 124 of the resection system 102 is coupled to the shaft 104 viaan opening 128 formed in the hub 124. The handpiece 122 may also includevarious internal shielding structures to mitigate contamination of thetissue fragments as they travel along a passageway 121 extending throughthe handpiece 122. For example, the handpiece 122 may include a flowdiverter 130 (FIG. 3B) which causes the tissue fragments to bypass themost commonly contaminated areas A of the handpiece 122. In analternative example, illustrated in FIG. 3C, a sterile sleeve 123 may beintegrated within the passageway 121 to prevent contamination of thetissue fragments by the handpiece 122. In examples, the sterile sleeve123 is made of a thermally-conductive material which is also selected tobe deformable, collapse-resistant and shear-resistant through the rigidtubing 131 and the barb 132.

Alternative examples of the handpiece 122 are shown with regard to FIGS.3D and 3E. In the example shown in FIG. 3D, the tissue fragments couldbe diverted to flow outside of the blade 203. For example, an outflowport 225 could be integrated on the hub 224 of the blade 203 andconnected with tubing 227 (FIG. 3E) which is attached to the filterassembly 120. An integral valve 229 (FIG. 3D) or separate valve 229′attached to the suction lever 206 of the handpiece 222 (FIG. 3E) couldbe used to control suction. Additionally, a small portion of aspiratedfluid could be diverted from the hub 224 to cool down the handpiece 222.In another example, illustrated in FIG. 3F, to fully cool down thehandpiece 322, aspirated fluid flowing through the outflow port 325 onthe hub 324 could be fed through a filter (not shown) and then back intothe hub 324, and then finally through the handpiece 322. In yet anotherexample, shown in FIG. 3G, the suction lever 406 of the handpiece 422may utilize ambient air 431 to control the suction of the blade 402 whentwo suction ports or inlets 436, 437 are present. The suction lever 406on the handpiece 422 controls the air 431 running backwards into the hub424, thus reducing the effective suction strength of the blade 402.

Turning now to FIG. 4A, an example of the filter assembly 120 of thisdisclosure is illustrated in more detail. A filter 140 is disposedwithin the internal volume 133 of the housing 134 for the collection oftissue fragments about an outer surface of the filter 140. In examples,the filter 140 is a hollow, tubular filter allowing suction to beapplied through the interior of the filter 140. However, other suitablefilters having any number of possible geometric shapes may be employed.As suction is applied, fluid flows through holes 141 in communicationwith the interior of the filter 140, causing the tissue fragments to becollected about the outer surface of the filter 140. In examples, a sizeof the holes 141 is selected to be smaller than a pre-selected size ofthe tissue fragments.

As shown in FIG. 4B, the filter 140 is coupled to the outlet 138 suchthat the filter 140 and the outlet 138 are removeable from the housing134 simultaneously. As stated above, the compressor 142 is extendablethrough a port 135 in the housing and configured to axially slide atleast partially within the housing 134 toward the outlet 138. Inexamples, the compressor 142 may slide within the housing 134 by amanual force exerted on a surface of the compressor 142. Alternatively,closing off the inlet 136 while suction is applied to the filterassembly 120 may act as a force on the surface of the compressor 142,causing the compressor 142 to advance toward to the outlet 138. As thecompressor 142 is moved toward the outlet 138, tissue fragments Fcollected within the housing 134 are compacted against outlet 138, thusallowing measurement of the volume of tissue fragments F harvested. Tofacilitate this, a portion of the housing 134 may be provided with atransparent surface 144 to allow direct visualization of the tissuefragments F. Furthermore, the transparent surface 144 may includemarkings 148 (FIG. 5B) to aid in the measurement of the volume of thetissue fragments F. If more tissue fragments are required, additionalaspiration could be applied. Notably, during aspiration of the tissuefragments F, a gap must be maintained between the compressor 142 and thefilter 140 so that the compressor 140 does not block the collection ofthe tissue fragments about the filter 140. In examples, a biasingmember, such as a spring 143 (FIG. 7A) may be provided to return thecompressor 140 back to its initial position away from the filter 140when the measurement of the tissue fragments F is complete.

Turning now to FIG. 5A, examples of the housing 134 of this disclosuremay include a shearing lip 150 at the proximal end of the housing 134and slidably disposed about a portion of the filter 140. A first portion150 a of the lip 150 is fixedly disposed within the housing 134 and asecond portion 150 b of the lip 150 is removeably disposed within acavity 151 of the outlet 138. Thus, the outlet 138 and the filter 140may be removed from the housing 134 without changing the position of thelip 150 relative to the housing 134. As the outlet 138 and the filter140 are removed from the housing 134 (FIG. 5B), the lip 150 acts toshear the tissue fragments off of the outer surface of the filter 140,thus leaving the tissue fragments within the filter assembly 120 andready for delivery to a repair site. After removal of the filter 140(FIG. 5C), a biocompatible agent may be introduced into the housing 134to facilitate the attachment of the fragments to the repair site afterdelivery. The agent may comprise any suitable biological or syntheticagent. For example, the agent may comprise hyaluronic acid, alginate,cross-linked alginate, collagen, fibrin glue, fibrin clot,poly(N-isopropulacrylamide), agarose, chitin, chitosan, cellulose,polysaccharides, poly(oxyalkylene), a copolymer of poly(ethyleneoxide)-poly(propylene oxide), poly(vinyl alcohol), polyacrylate,Matrigel, or mixtures thereof.

As shown in FIG. 6A, examples of the compressor 142 of this disclosuremay further include one or more asymmetrical wires 152 attached to thecompressor 142. For example, the wires 152 may be slidably receivedwithin grooves 154 on an outer surface of the compressor 142. The wires152 may be used for mixing the collected tissue fragments with theintroduced agent. Rotary motion is transferred to the wires 152 byrotation of the compressor 142 relative to the housing 134 to create amixture of agent and tissue fragments within the housing 134 (FIG. 6B).Notably, the wires 152 may be made of a deformable material such thatthe wires 152 do not impede axial movement of the compressor 142 throughthe housing 134 (FIG. 6C).

Turning now to FIG. 7A, an example of a delivery device 156 used todeliver the tissue fragments collected in the filter assembly 120 isshown. The delivery device 156 generally comprises a cannulated shaft155 and a handle 157. The handle 157 is configured to mate with acoupling portion 174 of the housing 134 (for example, a Luer or threadedfitting) of the filter assembly 120, as shown in FIG. 7B. A channel 160extending through the shaft 155 and the handle 157 of the deliverydevice 156 is configured for the passage of a plunger 158 insertedthrough the inlet 136 of the compressor 142 to deliver the tissuefragments out of a delivery end 161 of the shaft 155. In examples, adiameter of the channel 160 is selected to minimize resistance of thetissue fragments as the plunger 158 is advanced through the channel 160.A lip 196 surrounds at least a portion of the circumference of thedelivery end 161 of the shaft 155 and extends a distance radially fromthe shaft 155. A surface of the lip 196 is aligned with a portion of anopening 194 of the shaft 155, the surface being substantially planar.This configuration allows the lip 196 to be dragged over the repair siteduring tissue delivery while still leaving a smooth surface on therepair site. Advantageously, use of the delivery device 156 allowsdelivery of the tissue fragments to a repair site without direct humancontact with the fragments. However, in an alternative example of thedelivery device 556, shown in FIG. 7C, the handle 557 of the deliverydevice 556 may be provided with an access door 559 allowing directaccess to the tissue fragments, if desired.

As shown in FIG. 8A, a manual actuator 162, such as a thumb roller, maybe provided on a surface of the handle 157 of the delivery device 156for one-handed delivery of the tissue fragments to the repair site. Inexamples, as the actuator 162 is rotated, gear teeth 166 of an integralpinion gear 164 engage with corresponding teeth 168 on a surface of theplunger 158, causing the plunger 158 to move axially within the channel160. In alternative examples, not shown, the interface between theactuator 162 and the plunger 158 could be a frictional engagement. Infurther examples, shown in FIG. 8B, limiting the loss of tissuefragments around the actuator 162 can be accomplished by preventing therotation of the actuator 162 until mated with the plunger 158, and/orsmoothing the gear teeth 166 in one area B, while still allowing fullrotation of the actuator 162 (FIG. 8B).

Turning now to FIG. 9A, when inserted through the compressor 142, theplunger 158 and the compressor 142 advance together through the housing134 to push the tissue fragments into the channel 160 of the deliverydevice 156. The lip 150 now acts as a funnel to facilitate the flow ofthe tissue fragments into the channel 160. As the plunger 158 and thecompressor 142 are advanced together, the compressor 142 is preventedfrom further advancement by the first portion 150 a of the lip 150 (FIG.9B). Once the compressor 142 is stopped by the lip 150, a mechanismallows the plunger 158 to advance through the second portion 150 b ofthe lip 150 and into the channel 160 of the delivery device 156 (FIG.9C). One example of the mechanism is described below with regard toFIGS. 11A-C. However, other suitable mechanisms for controlling thisrelative motion between the compressor 142 and the plunger 158 throughthe housing 134 are contemplated by this disclosure.

Alternative examples of the plunger 658 of this disclosure canincorporate mixing wires 652 within the plunger 658, as shown in FIGS.10A and 10B. For example, the plunger 658 may be configured for thepassage of a deformable mixing wire 652. The wire 652 is configured tobe rotated and/or advanced within the delivery device 656 to further mixthe contents of the delivery device 656 before delivery to the repairsite.

Further details regarding the interface between the compressor 142 andthe plunger 158 are shown in FIGS. 11A-C. In order for the compressor142 and the plunger 158 to move together through the housing 134, amechanism is required to join them temporarily. In examples, themechanism is a cam lever 170 extending from an interior of the plunger158 through a slot 172 in the outer surface of the plunger 158. As shownin FIG. 11A, the cam lever 170 initially pushes against the inlet 136 atboth points “a” and “b”. As the inlet 136 and the plunger 158 areadvanced through the housing 134, the cam lever 170 eventually comesinto contact with a stationary feature (i.e., the distal end of thehousing 134) and, with further advancement, begins to pivot, firstlifting off of point “a” and then disengaging with point “b” (FIG. 11B).As the plunger 158 continues to advance, the cam lever 170 rotates to ahorizontal position within the plunger 158, allowing the plunger 158 tocontinue advancing while leaving the compressor 142 in place (FIG. 11C).In alternative examples (not shown), a rotary motion of the plunger 158relative to the compressor 142 could lock and unlock the plunger 158 andthe compressor 142.

Turning now to FIG. 12A, in operation, the resection system 102 of thetissue collection assembly 100 is brought into contact with a donor siteand the operator cuts a desired amount of donor tissue from the siteusing the cutting end 104 b. The vacuum source (not shown) aspiratesfluid and the cut tissue through the shaft 104 and the handpiece 122 tothe filter assembly 120. During aspiration, the fluid and cut tissuepass over the filter 140 (FIG. 4A) within the housing 134 where tissuefragments are isolated and/or retained on the outer surface of thefilter 140. In examples, following aspiration of the fluid and cuttissue, the inlet 136 of the compressor 142 may be closed off using, forexample, a valve, stop, plug, or other suitable device. The compressor142 may then be advanced within the housing 134 to compress the tissuefragments within the housing 134 for measurement of the volume of thefragments. Aspiration of the fluid and cut tissue may be repeated untila desired volume of tissue fragments is reached, at which point thefilter assembly 120 is removed from the resection system 102. The outlet138 and the filter 140 are then removed from the housing 134, causingthe lip 150 (FIG. 5A) to shear the tissue fragments from the outersurface of the filter 140. Optionally, a syringe or other instrument(not shown) containing a biocompatible agent is coupled to the housing134, for example, by a Luer lock or other suitable connection in thehousing 134. The agent is then injected into the housing 134 to mix withthe tissue fragments. In examples, deformable wires 152 attached to thecompressor 142 (FIG. 6A) may be rotated via rotation of the compressor142 relative to the housing 134 to mix the tissue fragments and theagent to promote even distribution of the tissue fragments within theagent.

As shown in FIG. 12B, once the desired mixture is collected within thehousing 134, the operator inserts the plunger 158 of the delivery device156 into the inlet 136 of the compressor 142 and advances the plunger158 and the compressor 142 together until the compressor 142 isprevented from further advancement within the housing 134. Thecompressor 142 may be latched into this position as the plunger 158continues to travel past the region of the actuator 162. The operatorthen manually actuates the actuator 162 on the handle 157 to advance theplunger 158 through the delivery device 156 for controlled applicationof the tissue and agent mixture to the repair site. Alternatively, themixture can be placed onto a tissue scaffold or used for furtherprocessing.

An alternative example of the filter assembly 720 is shown in FIG. 13.In the example of FIG. 13, suction is applied to the housing 734 throughan offset outlet 738 providing fluid flow about the outer surface of thefilter 740. As the suction is applied, fluid flowing through holes 741in communication with the interior of the filter 740 causes the tissuefragments to be collected about the inner surface of the filter 740. Inexamples, a size of the holes 741 is selected to be smaller than apre-selected size of the tissue fragments. The filter 740 of FIG. 13 mayfurthermore be configured for the passage of a syringe-type plunger 758through an interior of the filter 740 to deliver the tissue fragments tothe repair site.

In other examples, the filter 840 may be removeably disposed within thehub 824 of the blade 803, as shown in FIGS. 14A and 14B. In FIG. 14A, assuction S is applied, the filter 840 collects tissue fragments F on anexterior surface of the filter 840. In FIG. 14B, as suction S isapplied, the filter 840 collects tissue fragments F on an interiorsurface of the filter 840. Optional joints 890 extend between the filter840 and the cutting end 804 b of the blade 803 for facilitating removalof the filter 840 from the blade 803.

FIGS. 15A-C illustrate another example of a mixing wire 952 incorporatedinto the plunger 958. FIG. 15A shows the wire 952 housed within a track988 of the plunger 958 as the plunger 958 is inserted through thecompressor 942 within the housing 934 of the filter assembly 920. InFIG. 15A, the wire 952 is exposed beyond the distal end of the plunger958 and can be used to mix the tissue fragments F with the biocompatibleagent. As the plunger 958 advances through the compressor 942, theplunger 958 pushes the compressor 942 and the wire 952 together throughthe housing 934. As shown in FIG. 15B, when the plunger 958 is moveddistally along the full length of the housing 934, the compressor 942engages a latch 984 in the housing 934, preventing the compressor 942from moving proximally. In addition, a bent portion 986 of wire 952interferes with the compressor 942. As the plunger 958 continues to movedistally, the plunger 958 covers the wire 952 until the wire 952 bottomsout at the end of the track 988 on the surface 982 of the plunger 958.At this stage, the distal end of the plunger 958 and wire 952 aresubstantially flush. The plunger 958 and the wire 952 continue toadvance together within the housing 934 while the compressor 942 stayslocked within the housing 934 (FIG. 15C).

The assemblies and devices described herein may be considereddisposable, although they may also be reused upon sterilization, such asby gamma irradiation, ethylene oxide, formalin, hydrogen peroxide, orsodium hypochlorite. The filters and syringes discussed herein may becommercially obtained. In examples, the assemblies and devices, andtheir respective component parts, may be made of plastic, metal, orother suitable materials.

While the disclosure has been particularly shown and described withreferences to preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the spirit and scope of the presentapplication as defined by the appended claims. Such variations areintended to be covered by the scope of this present application. Assuch, the foregoing description of examples of the present applicationis not intended to be limiting, the full scope rather being conveyed bythe appended claims.

What is claimed is:
 1. A tissue collection assembly comprising: ahandpiece having a proximal end, a distal end, and a passagewaytherethrough; a cannulated shaft attached to the distal end of thehandpiece in fluid communication with the passageway, a distal end ofthe shaft configured to receive tissue fragments; and a filter assemblyremoveably attached to the proximal end of the handpiece in fluidcommunication with the cannulated shaft via a tube extending from theproximal end of the handpiece such that a distal end of the filterassembly is spaced apart from the proximal end of the handpiece, thefilter assembly comprising: a housing allowing direct visualization ofan internal volume of the housing; and a filter disposed within theinternal volume of the housing for collecting the tissue fragments on asurface of the filter.
 2. The tissue collection assembly of claim 1,further comprising a compressor extendable through the internal volumeof the housing for compressing the tissue fragments.
 3. The tissuecollection assembly of claim 2, wherein the handpiece further comprisesrigid tubing and a barb in fluid communication with the filter assembly.4. The tissue collection assembly of claim 3, wherein the compressorcomprises an inlet for removeable attachment to the barb.
 5. The tissuecollection assembly of claim 1, wherein the housing comprises aremoveable outlet for attachment to a vacuum source.
 6. The tissuecollection assembly of claim 5, wherein the filter is coupled to theoutlet such that the filter and the outlet are removeable from thehousing simultaneously.
 7. The tissue collection assembly of claim 1,wherein the housing further comprises a shearing member slidablydisposed around the filter for removing the tissue fragments from thefilter.
 8. The tissue collection assembly of claim 1, further comprisinga flexible shield adjacent the distal end of the shaft.
 9. The tissuecollection assembly of claim 1, wherein the handpiece is a motorizeddrive unit.
 10. The tissue collection assembly of claim 1, wherein theassembly further includes a finger-engageable lever on a surface of thehandpiece to control flow of the fragments through the passageway of thehandpiece.
 11. The tissue collection assembly of claim 1, wherein thehandpiece comprises at least one internal structure to preventcontamination of the tissue fragments by the handpiece.
 12. The tissuecollection assembly of claim 11, wherein the at least one internalstructure is a flow diverter.
 13. The tissue collection assembly ofclaim 11, wherein the at least one internal structure is a sleeveintegrated with the passageway of the handpiece.
 14. The tissuecollection assembly of claim 1, wherein the filter is a hollow, tubularfilter, and the surface of the filter comprises holes in communicationwith an interior of the filter.
 15. The tissue collection assembly ofclaim 1, wherein the filter assembly is coupleable with a deliverydevice to deliver the tissue fragments to a repair site.
 16. The tissuecollection assembly of claim 1, wherein the tissue fragments areselected from one of cartilage, bone, fat, meniscus, tendon, andligament tissue fragments.